chem / prac-9-aim.mdon commit [chem] proteins (3e6f607)
   1# Experiment 9 - Effect of temperature and pressure on equilibrium
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   3To determine the effect of the temperature and pressure of an equilirium environment on the direction of the equilibrium reaction. Temperature is tested by adding methyl violet indicator to a solution of phosphoric acid which shows the concentration of ionised H+ and H2PO4- ions. Pressure (inversely proportional to volume) is tested with dinitrogen tetroxide and the colour change is observed.
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   5N2O4(g) <-> 2NO2(g)
   6  clear <-> brown
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   8Explain colour changes - net forward/back reaction
   92 page question
  10Do not duplicate
  11
  12What was the change to equilibrium system? (do not copy method)
  13(1 mark for each test)
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  15Vertical lines on plots
  16(selection of graphs)
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  18Reaction conc initially > product conc
  19Two marks on x-axis - init. & funal equilibrium
  20Rule graphs
  21Lines may cross
  22
  23H33PO4 - each product concentration is equal (dissociation of acid) - one line
  24Fe3+ + SCN- - each reactant is not necessarily equal concentration
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  2690 marks total
  2717 marks from results
  281 mark/box on first question (table)